/Engine/Source/Runtime/MovieScene/Public/Sections/MovieSceneSubSection.h
Gets the playrange of the inner sequence, in the inner sequence's time space, trimmed with any start/end offsets, and validated to make sure we get at least a 1-frame long playback range (e.g. in the case where excessive trimming results in an invalid range).
bool GetValidatedInnerPlaybackRange ( [TRange](API\Runtime\Core\Math\TRange)< [FFrameNumber](API\Runtime\Core\Misc\FFrameNumber) > & OutInnerPlaybackRange ) const